The present invention relates to concrete raising, more particularly to an apparatus for raising concrete members and maintaining same in the new position by the use of a mud or grout, and more particularly to a portable mud pump and mixing tank for introducing the mud or grout into a cavity under the raised concrete member.
Generally when concrete or cement members such as flat slabs, sidewalk sections, driveways, patios, steps, and curb and gutter sections sink due to a settling of soil thereunder, etc., the sections of concrete are removed and new concrete poured, which is time consuming, costly, and additionally requires the disposal of the removed concrete sections.
The method described and claimed in above referenced application Ser. No. 09/399,074 provides a solution to the problem of sunken concrete members and involves raising the members whereby such need not be removed and replaced. In the case of sunken concrete members, the member is lifted to its original position, or slightly higher, and a mud or grout is pumped into the cavity beneath the raised concrete member which functions to retain the member in its raised position. The mud pump produces sufficient pressure that in some instances the pumped mud will raise the concrete member.
Mud or slurry pumps are well known, as exemplified by U.S. Pat. No. 4,718,826 issued Jan. 12, 1988, U.S. Pat. No. 3,326,135 issued Jun. 20, 1967, U.S. Pat. No. 3,507,347 issued Apr. 21, 1970, and U.S. Pat. No. 4,500,267 issued Feb. 19, 1985. These prior mud pumps are either large units (not readily portable) or are small, manually operated, low volume units. The mud pump and mixing tank of the present invention are readily portable, small enough to fit in a corner of a pickup truck, deliver a sufficient pressure and flow rate of mud, and are easily cleaned and maintained. The portable mud pump of this invention basically consists of an air cylinder, pump body and reversing valve assembly. The mixing tank of this invention includes mixing impellers, stirring rods, and ambulator paddles which mix water and mud mixture to form a mud and prevent it from clumping during mixing and distribution to the pump. Utilizing the method of Ser. No. 09/339,074 an apparatus (pump and mixing tank) of the present invention, concrete or cement members can be repositioned to their original position in less time and at less cost than by removal and replacement.
It is an object of the present invention to provide an apparatus for use in repositioning concrete members to their original position.
A further object of the invention is to provide a mud pump and mixing tank utilized for raising sunken concrete members, which includes providing a mud or grout thereunder for maintaining the member in its raised position.
Another object of the invention is to provide a portable mud pump and mixing tank which is of small size yet delivers sufficient pressure and flow rate to effectively fill cavities under raised concrete members, and is easily cleaned and maintained.
Another object of the invention is to provide a small, portable grout or mud pump basically consisting of an air cylinder and connected pump body having a double acting piston therein, and a reversing valve assembly connected to a mud or grout supply tank via a check valve.
Another object of the invention is to provide a grout or mud mixing tank for supplying a portable pump and includes stir rods, mixing impellers and ambulator paddles mounted on a single drive shaft within a housing.
Other objects and advantages of the present invention will become apparent from the following description and accompanying drawings. The present invention basically involves a mud pump and mixing tank for use in repositioning of concrete or a cement member to its original position. The apparatus of the present invention may be utilized in the return of the member to its original location and to fill the cavity thereunder with a mud or grout which maintains the member in its original position. The portable mud pump and mixing tank are small and fit very easily in a corner of a pickup truck bed, deliver a sufficient pressure and flow rate of consistently mixed mud to enable filling of cavities under concrete members, and are easily cleaned and maintained. The mud pump basically comprises an air cylinder (with a reciprocating piston), pump body, and a reversing valve assembly. The reciprocating piston is pneumatically driven and mud is drawn from the mixing tank into the pump body on the intake stroke, and that same mud is pumped or forced from the pump body by the piston or ram on the output stroke through a hose into the cavity or point of use. At the end of each stroke, a limit switch actuates an air valve assembly which reverses the air flow direction and thus the direction of movement of the reciprocating piston within the pump body which provides a substantial flow of mud to the point of use. The mixing tank basically comprises a housing with openings for the entry of water and mud mixtures, a discharge nozzle, a drive shaft on which are mounted stir rods, large and small impellers, an ambulator paddle assembly, and a mix/feed control.